Modern display technology may be implemented to provide head worn displays (HWD) and to see through the display and to see information (e.g., images, text, or the like) in conjunction with the see through display. Such displays can be implemented in a variety of contexts, for example, defense, transportation, industrial, entertainment, wearable devices, or the like.
In various HWD systems, an image may be reflected off a transparent projection surface to a user's eye to present an image in conjunction with a real worldview. HWDs provide a projection system and a lens that includes a holographic optical element (HOE). The projection system and the lens can be mounted to a frame to be worn by a user, for example, glasses, a helmet, or the like. During operation, the projection system projects an image onto an inside (e.g., proximate to the user) surface of the lens. The HOE reflects the image to an exit pupil (or viewpoint).
Generally, manufacturing an HOE first requires shaping the raw material of the HOE so that it can be used with a lens of a HWD, glasses or the like. Subsequently, an HOE recording step is performed. For example, HOE recording may be achieved, in one example, by recording an interference pattern of an wavefront object beam and a wavefront reference beam.
The foregoing HOE manufacturing technique is a reasonable approach if the final shape of the HOE is flat or cylindrical, as the HOE may be manufactured using a standard production process (e.g., roll-to-roll). However, HOEs that require complex shaping (e.g., spherical, toric or freeform) are not straightforwardly manufactured using conventional methods.